How a Roll Coater Works?

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1. Understand the working principle of the roll coater

Roll coaters are often used to industrially apply liquids to the surface of a part. Roll coaters can be used to apply liquid adhesives, paints, oils and coatings such as varnishes or clear topcoats. Roll coaters can take many forms, from simple paint rollers to complex coaters with multiple rollers. A roll coater works by transferring a layer of coating from the surface of the roller to the surface of the part. When this happens, a phenomenon known as "film splitting" occurs. The coating on the surface of the roll splits - part of it remains on the roll and part of it sticks to the surface of the part. The percentage of coating that adheres to the part (substrate) depends on the surface characteristics of the roller and substrate.